1. Field
One or more embodiments of the present invention relate to a secondary battery.
2. Description of the Related Art
Secondary batteries are rechargeable batteries and are widely used in small mobile devices such as smart phones, very slim laptop computers, tablet personal computers, personal digital assistants, camcorders, and digital cameras, or medium and large electronic devices such as electric vehicles, hybrid electric vehicles, electric bicycles, uninterruptible power supplies (UPSs), and energy storage systems (ESSs).
Several tens of secondary batteries connected in series or parallel may be used in a medium or large electronic device. Because secondary batteries are rechargeable, some secondary batteries are used for long periods of time and therefore are designed to stably maintain mechanical and electric connections of elements of the secondary batteries.